1. Field of the Invention
The present invention relates to a method and apparatus for aligning equipment on board a carrier vehicle more particularly on board an aircraft.
2. Description of the Prior Art
It is known that some pieces of equipment carried on board a vehicle must occupy fixed and precise positions with respect to each other and/or with respect to a reference system of this vehicle. Such equipment is, for example for an aircraft, that used for navigation, such as the gyrocenter, gyrometers or accelerometers, or else for detection, such as a radar, or else again for combat, such as arms and their aiming systems. Such equipment must be "aligned" with the reference system of the vehicle and their respective positions must be "harmonized".
In the present state of the technique, two alignment methods are essentially known:
(a) the first one consists in setting up the equipment in adjustable parts of racks, whose fixed parts are integral with the vehicle. The mechanical alignment of these adjustable rack parts (and so of said equipment) takes place during the phase of installing the equipment on board. Such a method is generally used for alignment of gyrocenters mounted on aircraft of helicopters.
This first method requires long and complicated measurements, using reference points fixed to the structure of the vehicle and sighting marks or levels, for determining the longitudinal axis of said vehicle, as well as the horizontal reference plane thereof.
For this, a distance measuring system is used provided with theodolytes.
It will be noted that, in the use of this first alignment method:
the measurements must be made for each piece of equipment to be aligned;
these measurements calculate the degree of misalignment between the various pieces of equipment and the vehicle and call for precise mechanical positioning correction operations, appropriate for each piece of equipment in turn, until all said pieces of equipment are "aligned" with respect to the axes of the aircraft. This requires long and delicate operations.
(b) in the second alignment method, during the construction of the structure of the vehicle a precise fitting plane is provided and the equipment is thereafter positioned on the fitting plane. This method is often used for positioning doppler radars and vertical gyroscopes in aircraft and helicopters.
It will be noted that this second method, during construction of the structure of the aircraft, involves the precise mechanical alignment of a reference assembly. This assembly, once aligned and immobilized, makes it possible to machine the fitting plane precisely and form therein positioning bores intended to receive centering studs integral with each piece of equipment.
Thus, when this second method is used, it requires the formation of as many fitting planes as there are pieces of equipment to be aligned.
The use of this second method is therefore also long, complex and expensive.